1. Field of the Invention
The present invention relates to a combined machine for printing and scanning having a head assembly including a printer module and a scanner module, and more particularly to an improved combined machine for printing and scanning which is capable of obtaining consistent output values with an image pickup device by using an elongated light source mounted on the printer at the rear end of the head module over which the head traverses while traversing a document, the light source for scanning being separate from the scanner module and irradiating equal quantities of light over the whole area for scanning. The invention is capable of drying ejected ink in a short time by heat radiated from the light source.
2. Description of the Related Art
Nowadays, office automation facilities or equipment, such as a printer and a scanner, are widely used. These facilities, having high efficiency, are developed with enhanced features and, thus, cause the price of these products to become high. The present invention has been produced to lessen the economic burden of a user by developing a combined machine for printing and scanning.
Examples of contemporary printers in the art may be grouped in three areas. The first area includes those combined printer-scanner head assemblies with a self-contained light source. For example, U.S. Pat. No. 5,047,870 to Filo, entitled Image Reproduction System Utilizing Single Operation Scanning/Reproducing, describes a traversing head assembly which contains a light emitting diode and photo transistor connected by a cable to a processing circuit. The head assembly also includes a thermal print head. Both the scanner and print head address the same document fed thereunder. The second area includes those devices which include a fill-length head and/or light source. U.S. Pat. No. 3,676,586 to Uno, entitled Thin-Window Image Pick-Up And Recording Tube, describes a thin-window image pick-up and recording tube including a full-length flourescent layer. An electron beam is emitted from an electron gun which causes the flourescent layer to luminesce and irradiate an object or sensitized sheet. When the device is used for scanning, the strength of the electron beams emitted through the document varies according to the existence or shading of images on the document. The flourescent plate luminesces in a corresponding pattern. U.S. Pat. No. 3,899,035 to Rothgordt, entitled Facsimile Transmitting Receiving System With Fibers Having A Conductive Coating, provides an array of a lined fibers that emit light and sense the intensity of light reflected from a document. U.S. Pat. No. 5,040,074 to Stemmle, entitled Full-Width Simultaneous Read/Write Copier, provides a full-width head including an LED array and lens for scanning, as well as a printing bar. Images are read from documents advanced by one platen, and images are formed on other documents advanced by another platen. A third group pertains to combined, or simultaneously driven, printing and scanning elements. U.S. Pat. No. 4,303,936 to Shaw, entitled Structure For And Method Of Reproduction, includes a single light source, or plurality of light sources, directing light through a original document to light sensors. Signals are amplified and directed to a printer which forms images on a document advanced separately from, but in synchronicity with, the document being scanned. U.S. Pat. No. 4,424,523 to Snelling et al., entitled Read/Write Bar For Multi-Mode Reproduction Machine, describes a full-width head containing an array of LED elements and optical fibers. The device scans images from a document fed across one platen, and imparts a latent image onto a photosensitive drum, a technique that is conventional in electrophotographic processes. U.S. Pat. No. 4,635,130 to Oi, entitled Image Reading/Recording Apparatus, describes a full-width head including a recording portion and a reading portion proximate to a roller. U.S. Pat. No. 2,776,336 to Clauer, entitled Dual Function Facsimile Apparatus includes a carriage which moves scanning and reproducing head relative to individual document and recording sheet feed rollers. The scanning unit traverses the width of the document advanced by a platen. Two elongated flourescent lamps are fixed to the frame and illuminate the entire width of the document being scanned. The print head is located on the opposite side of the carriage, and, with an ink-fed stylus, imprints indicia on recording papers advanced by a different platen than that which advances the document to be scanned.
I have found that the conventional combined printing and scanning machine has several problems. First, as it takes much time to dry ink ejected by a printer head unit of the ink-jet printer on the paper, it is difficult to perform printing at high speed. Occasionally, as the paper feed roller contacts on an area where ink is not dried completely, ink can spread or smear on the paper. Moreover, as the conventional combined printing and scanning machine typically has a small lamp inside of the scanner module, disassembly of the lamp is difficult, and often requires inconvenient after-sales service.